According to polls conducted by the National Sleep Foundation in recent years, the number of Americans who get enough sleep for good health (about 7 to 8 hours per night) has decreased, with 20 percent reporting that they get less than six hours of sleep per night on average. This is a concern for a lot of health reasons, but one that's getting more attention these days is the link to weight gain and obesity.

There can be many reasons why someone isn't getting enough good sleep. Increased artificial lighting in our cities and blue screen lighting from our smart phones, televisions and computers can play havoc with the biorhythms necessary for healthy sleep patterns. Other factors include shift work, sleep apnea and other sleep disorders, hormonal changes during menopause and high caffeine use (such as in energy drinks).

Ignoring or resisting the body's signals to rest can eventually create a state of chronic sleep deprivation. It's not uncommon in our culture for some people to take pride in getting by on little sleep. But sleep deprivation isn't a sign of strength. Instead, it's something to be concerned about.

While all the causal factors pertaining to sleep deprivation and weight gain haven't been clearly established, the research has been giving some clues.

One possibility is that sleep deprivation affects hormones that affect hunger and appetite.

Ghrelin is the hormone that has a role in telling us when to start eating. Leptin, on the other hand, is the hormone that signals when to stop eating. Lack of sleep leads to more ghrelin and less leptin, making it harder to fend off weight gain.

There are other factors that may tie sleep deprivation to weight problems:

• More time to eat. With more time awake there's more time to sense hunger and satisfy it with more calories.

• Fatigue. We may deny we're tired, but our bodies know better. At these times, we're more vulnerable to poor food choices and overeating. Tired people also are less likely to exercise.

• Metabolism. Our metabolism tends to be higher early in the day and slows down at night. So if we're chronically awake and eating during those slower times, it's not hard to imagine what that can do to the waistline.

• Carb and fat overload. When we're tired we tend to reach for comfort foods. We may think a dose of sugary, fatty foods will give us quick energy and make us feel better, but any such benefit will be short-lived.

Managing weight successfully requires attention to much more than just the "right" diet.

If you consider how complicated the body and brain are, it makes sense that we need to go about this issue using our smarts.

In this case, assessing how well we meet our sleep needs can make a big difference in how easily we'll achieve our weight goals.

For some, simple lifestyle changes will improve sleep. Others may need to see a specialist and be evaluated for a possible sleep disorder. Psychological factors such as depression can also be at the root of sleep problems.

Whatever the cause, eliminating sleep deprivation will likely help with weight management.

How often is dieting advice as comforting as being told to get a good night's sleep?

Dr. Lavinia Rodriguez is a Tampa psychologist and expert in weight management. She is the author of "Mind Over Fat Matters: Conquering Psychological Barriers to Weight Management." Send questions to her at [email protected]

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